Device for reducing the insulating-strips of commutators.



Bi 0. SWAIN 82; J. S. TIMMONS. DEVICE FOR REDUCING THE INSULATING STRIPS O]? GOMMUTATORS. APPLICATION FILED APR. 14, 1914.

1,116,158, Patented Nov. 3, 1914.

inents of a commutator.

and the slot is preferably 11716 BENJAMIN 0. ZSWAIN BEVIC ntion filed April i l.

To all whom it mm comer/'1 Be it known tlnit w BENJABHN O. SWAIN and Jonx li'niioirs, cit-i' ens ot'the United States, residing in ihiladelphia, Pennsylvania, have innnted c stein linprovements in Devices for ucing f Insulating-Strips of Coinniutators, of which the following is a specification.

This invention relates to 2: machine for reducing the heightof sheets of mice, or other hard, non-resisting, insulating material, which are placed between the seg- It is now found necessary to reduce, from time to tine, the sheets of mica as the commutator wear, so that the mica will always below the surface of said segments.

One object of this inven vide a simple and. el'iect'rc n ichine cutting the mica se inrating s ups and t provide an accurate machine, so as to pre vent the saw or milling tool from cutt n into the side Walls and. destroying the commutator segments,

A further object of the invention is to provide 'a' device of the character shove described which can be firmly held in the hand and which. can be ")(l'.l \f guided over the face of the 'comrnut; n r.

A still further object of the invention. is to provide, means for removing the mica dust from the groove es the cutting 1rd coeds.

These dbjects and other advantageous ends We attain in the following manner, reference being had to the accompanying draw- .ings in which 2- Figure 1, is it perspective view illustratingour improved device for cutting the insulating strips of coininutators, one of the handles being broken away; Fig. 2-, is

an inverted plan view; F 3, is an end View; and. Fig. 4, is alongitudinal sectional view on the line aa, Fig. 2-. Referring to the drawings,

2, 2 are the handles one scour side of the body shown, and l the forward end.

The body is slotted 3, or

4, d are blocks ada Projecting from each at the outer end of QFFI IQE,

Let er 2 m- Patented Nov, 3, 191%. Serial No. 831,841.

extending narallel with the body 1; these runners can be of any length desired.

lly adjusting the blocks vertically in the slots 3 the device can be properly adjusted with respect to a commutator of a given diameter so that the sawor milling tool 7 will make a cut of the proper depth This is.clearly illustrated in Fig. 3, the runner 6 bearing upon the OQILUQutZttOI on each side of the center, as shown,

h'loun'ted on a projection 8 at the forward end of the body 1- is a spindle 9 located in an extended hearing 10. This spindle cor-- i'ies the circular saw or milling tool '7 one end and is shaped at the opposite end to receive the coupling of a flexible shaft, in the present nstance. Other means of driving the spindle may be resorted to with out departing from the essential feat of the invention.

The body 1 has it slot 11 in its underside extending its full length in line with of a greater width than the saw or milling; tool 7, and mounted in this slot are narrow guide wheels 12, which rotate {freely on spindles 13 These Wheels are iii line with the saw Tend do not project so deeply into the he f as the saw.

When the device is moved over an 3131221- prevents the saw from cutting into the side walls of the metallic segments.

In order to prevent the dust from econ Y mulating in the grooves, We form a passage ii in the body and connect an inclined nozzlc 15 with this passage; the nozzle being in line with the rear of the saw. The passage it is coupled to a pipe 16, which is attached to any source of air supply by a hose.

The operation is as followsz-The gnidingrunners are adjusted according to the diameter of the armature to be cut so to regulate the depth of the hen": made by the saw. Then the tool is grasped in both hands and, as the saw rotates, it is fed slowly into the space between the two segments of thoconimutotor, cut ing down the a strip to a depth below the surface of commutator. As the device is, fed forthe first guidewheel enters the groove guide the saw or milling tool in a straight course. l't hen the cut 1s completed the tool then the second guide Wheel, which v is lifted oil the work and is adjusted to the next space.

- By the use of this tool the armature need not be removed from the dynamo or motor, and there is no complicated mechanism for attaching or locating the parts one in respect to the other to make the proper cut.

Ty having the two handles and the body of sufificient weight, an operator can steady the work and can hold it in the proper position, and when the guide wheels enter the groove they prevent any swerving action of the cutter, which would injure or destroy the segments of the commutator.

In some instances, a single guide wheel may be used instead of the two wheels shown, or a single fixed guide may be located within the slot, which will enter the groove made by the saw so as to keep the saw in a-linement.

Other means of driving the spindle may be resorted to without departing from the essential features of the invention, and, in some instances, the spindle may be driven from an electric motor carried the body portion; the spindle being geared to the armature shaft in any suitable manner, and, when amotor is mounted on the body portion, a fan may be used for removing the dust from the kerf, taking the place of the air pressure hose.

lVe claim 1. The combination in a device for reducing the height of an insulating separating strip of a commutator, said device consisting of a body portion; a rotating cutter mounted thereon; and a guide back of the cutter arranged totravel in the kerf made by the cutter.

2. The combination in a device for reducing the height of the insulating separating strip of a commutator, said device condirectly by sisting of a body portion; a-rotating cutter; and a guide wheel back of the cutter.

3. The combination in a de ice for reducing the height of the insulating separating strip of a connnutator, of abody portion; a transverse shaft mounted at one end of the body portion; a saw mounted on the shaft; a guide back of the saw; guides on each side of the body portion; a vertically adjustable runner adapted to each guide, the horizontal portion of the runners extending beyond the end of the saw; and handles by which the tool is manipulated.

The combination of a body having alongitudinal slot in its underside and a projection at the forward end at one side of the slot; a horizontal shaft mounted in the projection; a saw or milling tool mounted on the shaft in line with the slot; guide wheels mounted in the slot in line with the saw; and vertically adjustable runners secured to the body portion at each side.

5. The combination of a body portion having a handle at each side; a shaft mounted on the body portion; a saw or milling tool mounted on the shaft, the body portion having a slot in its underside in line with the saw; a guide in the slot; runners secured to the body portion; and an air blast passage in the body portion having a nozzle in line with the saw so that the dust caused by the cutting will be removed as ther tool travels.

In testimony whereof, we have signed our names to this specification, in the presence of two subscribing Witnesses.

BENJAMIN O. SWAIN. JOHN S. TIMMONS.

Witnesses:

, CLYDE T. MQYER,

W A. Barn. 

